1. Field of the Invention
The present invention relates to an armature including an insulator and more specifically to a motor including the armature.
2. Description of the Related Art
In JP-A 2004-140964, an insulator is disclosed in which guide grooves are provided in the side surfaces so that coils are arranged in the guide grooves and wound around the insulator.
Moreover, in JP-A 2003-79080, an insulating member which is constituted so as to fit two insulating member pieces to each other is disclosed. Fitting portions which are fitted so as to overlap each other are installed in the tip of each insulating member piece. The fitting portions secure the minimum thickness size needed for the strength and the insulation performance. Thereby, the portion in which the fitting portions are overlapped with each other is necessarily thick.
As one way for improving motor performance, there is an improvement of a space factor of coils. If the coils are arranged and wound around the insulating member as in JP-A 2004-140964, the space factor of coils can be improved because the coils can be densely wound.
Moreover, if the thickness of the insulator is thin, the space factor of the coils can be improved because the space for accommodating the coils can be increased.
However, in the case of the insulating member like JP-A 2003-79080, in order to make the thickness of the fitting portions be the same as those of the other portions of the insulating member pieces, the fitting portions become thinner than the other portions of the insulating member pieces by the amount of overlap.
In addition, if the thickness of the insulation member pieces is thinned to the utmost limit, the thickness of the fitting portions is further thinned. As a result, in addition to the concern that strength of the fitting portions is decreased, there are also concerns that the fitting portions may be easily deformed such that a constant shape may not be stably held.
As a result, when the pair of insulating member pieces is fitted to magnetic tooth portions, there are concerns that the fitting portions of the pair of insulating member pieces may not be appropriately fitted and may be damaged.